Online Questions and Answers Topic Outline
- MCQs in Bit and and Binary Transmission
- MCQs in Signaling Rate
- MCQs in Error Probability, Digital Filtering, Switching, Packet Circuit, Vertical Circuit
- MCQs in Open systems Interconnection
- MCQs in Multiplying, Modulation and Synchronization
- MCQs in Pulse Code Modulation, Companding, Encoding, Bandwidth and Signal to Noise Ratio
- MCQs in Delta Modulation, Slope Overload, Adaptive Delta Modulation, Codes and Protocol
- MCQs in Error Detection and Correction, Digital Carrier systems
- MCQs in Frequency Shift Keying, Phase Shift Keying, Differential Phase Shift keying
- MCQs in DC nature of data transmission, loops, Neutral and Polar
- MCQs in Binary transmission and the concept of time
- MCQs in Asynchronous and Synchronous, timing, Distortion, Bits, band, WPM
- MCQs in Data Interface standards, Data input/output devices
- MCQs in Digital Transmission on analog channel, Modulation-demodulation schemes parameters
- MCQs in Circuit conditioning, Modem Applications
- MCQs in Serial and Parallel Transmission
MCQs in Digital and Data Communication Networks Series
Following is the list of multiple choice questions in this brand new series:
Continue Practice Exam Test Questions Part VI of the Series
251. If the active time of the binary pulse is less than 100% of the bit time
- A. Non return to zero
- B. Bipolar
- C. Unipolar
- D. Return to zero
252. It is a popular type of line encoding that produces a strong timing component for clock recovery and does not cause wandering
- A. Digital biphase
- B. diphase
- C. Manchester code
- D. Any of these
253. Statistical TDMs are also called
- A. Intelligent TDMs
- B. Asynchronous TDM
- C. Stat mux
- D. Any of these
254. A chip that combines the codec and filter functions in the same LSI chip
- A. Monolithic
- B. Combo chip
- C. Film IC
- D. Hybrid chip
255. It is the basic building block of FDM hierarchy
- A. Character channel
- B. Broadband channel
- C. Message channel
- D. Information capacity
256. It is the next higher level in the FDM hierarchy above the basic message channel and consequently is the first multiplexing step for combining message channels
- A. Supergroup
- B. Group
- C. Mastergroup
- D. Jumbogroup
257. It is the modulating signal in a communications system
- A. Broadband
- B. Baseband
- C. Carrier
- D. Any of these
258. What type of mastergroup that can be further multiplexed and used for higher-capacity microwave radio systems?
- A. A600
- B. U600
- C. L600
- D. L400
259. It is essentially the same with FDM, where several signals are transmitted using different carriers, occupying non-overlapping bands of frequency and wavelengths.
- A. Time division multiplexing
- B. Wave division multiplexing
- C. Space division multiplexing
- D. Frequency division multiplexing
260. In order to separate channels in the TDM receiver, it is necessary to use
- A. AND gates
- B. bandpass filters
- C. differentiation
- D. integration
261. To separate channels in an FDM receiver, it is necessary to use
- A. AND gates
- B. bandpass filters
- C. differentiation
- D. integration
262. In FDM, multiple signals
- A. transmit at different times
- B. share a common bandwidth
- C. use multiple channels
- D. modulate one another
263. Frequency modulation in FDM usually accomplished with a
- A. reactance modulator
- B. varactor
- C. VCO
- D. PLL
264. Which of the following is not a common LAN medium?
- A. twin lead
- B. twisted pair
- C. fiber-optic cable
- D. coax
265. A mainframe computer connected to multiple terminals and PCs usually uses which configuration?
- A. bus
- B. ring
- C. star
- D. tree
266. How many voice channels are there in supermaster group?
- A. 300
- B. 900
- C. 3600
- D. 10800
267. In a PAM/TDM system, keeping the multiplexer and DEMUX channels step with one another is done by a
- A. clock recovery circuit
- B. sync pulse
- C. sampling
- D. sequencer
268. It is the process of volume compression before transmission and expansion after detection.
- A. pre-emphasis
- B. de-emphasis
- C. coding
- D. companding
269. Which of the following is correct?
- A. The bit rate may be greater than the baud rate
- B. The baud rate may be greater than the bit rate
- C. The bit and baud rate are always the same
- D. The bit and baud rates are not related
270. Function of data link protocol that coordinates the rate at which data are transported over a link and generally provides an acknowledgement mechanism that ensures that data are received in the destination.
- A. Flow control
- B. Line discipline
- C. Polling
- D. Selection
271. A classification of protocol, which is a discipline for a serial-by-bit information transfer over data communications channel.
- A. Message oriented
- B. Bit-oriented protocol
- C. Clock oriented protocol
- D. Asynchronous protocol
272. A LAN device that interconnects two or more device running identical internetwork protocols.
- A. Bridges
- B. Gateways
- C. Switches
- D. Routers
273. The magnitude of a quantum in quantization of PCM codes.
- A. Maximum decodable voltage
- B. Dynamic range
- C. Resolution
- D. Coding level
274. It comprises of either a single L600 mastergroup or up to three U600 mastergroups
- A. Message channel
- B. Radio channel
- C. Baseband channel
- D. Wide channel
275. It is a multiplexing system similar to conventional time-division multiplexing except that it was developed to be used with optical fibers
- A. SONET
- B. Frame relay
- C. ATM
- D. X.25
276. Higher order TDM levels are obtained by
- A. dividing pulse widths
- B. using the a-law
- C. using u-law
- D. forming supermastergroups
277. Results when the sample exceeds the highest quantization interval
- A. Overload distortion
- B. Quantization error
- C. Quantization noise
- D. Granular noise
278. The event which marked the start of the modern computer age was
- A. design of the ENIAC computer
- B. development of Hollerith code
- C. development of the transistor
- D. development of disk drives for data storage
279. A forward error correcting code corrects errors by
- A. requiring partial transmission of the entire signal
- B. requiring retransmission of the entire signal
- C. requiring no part of the signal to be transmitted
- D. using parity to correct the errors in all cases
280. The carrier used with a BPSK demodulator is
- A. Generated by an oscillator
- B. The BPSK signal itself
- C. Twice the frequency of the transmitted carrier
- D. Recovered from the BPSK signal
281. Digital signals
- A. do not provide a continuous set of values
- B. represent values as discrete steps
- C. can utilize decimal or binary systems
- D. all of these
282. Each signal in an FDM signal
- A. modulates the main carrier
- B. modulates the final carrier
- C. is mixed with all the others before modulation
- D. serves as a subcarrier
283. In digital modulation, if the information signal is digital and the amplitude of the carrier is varied proportional to the information signal.
- A. Quaternary Shift Keying (QAM)
- B. Phase Shift Keying (PSK)
- C. Frequency Shift Keying (FSK)
- D. Amplitude Shift Keying (ASK)
284. Slow speed modems
- A. FSK
- B. BPSK
- C. QPSK
- D. QAM
285. The data rate for IEEE 802.11b is _____.
- A. 10 Mbps
- B. 1.544 Mbps
- C. 2.048 Mbps
- D. 11 Mbps
286. Type of analog companding used in the United States and Japan
- A. log-PCM companding
- B. A-law companding
- C. u-law companding
- D. any of these
287. A rule of procedure that defines how data is to be transmitted is called
- A. handshake
- B. error-detection
- C. data specifications
- D. protocol
288. A longitudinal redundancy check produces
- A. block check character
- B. parity bit
- C. CRC
- D. error correction
289. Multiplexing is the process of
- A. Several signal sources transmitting simultaneously to a receiver on common frequency
- B. Sending the same signal over multiple channels to multiple destinations
- C. Transmitting multiple signals over multiple channels
- D. Sending multiple signals simultaneously over a single channel
290. What is the relationship of bit rate and baud in QPSK and 8-PSK?
- A. bit rate is greater than baud
- B. bit rate is always less than the baud
- C. bit rate is never greater than the baud
- D. bit rate is slightly less than the baud
291. A common method of achieving carrier recovery for BPSK
- A. Trellis code
- B. Bandwidth efficiency
- C. Squaring loop
- D. Carrier recovery
292. What is the relationship of bit rate and baud in FSK and PSK?
- A. greater than
- B. slightly greater than
- C. less than
- D. equal
293. The modulation used in FDM telephone system is
- A. AM
- B. FM
- C. SSB
- D. PSK
294. In digital modulation, a diagram which is similar to phasor diagram except that the entire phasor is not drawn and only the peaks of the phasor are shown
- A. constellation diagram
- B. Venn diagram
- C. phasor diagram
- D. schematic diagram
295. Digital signals may be transmitted over the telephone network if
- A. their speed is low enough
- B. they are converted to analog first
- C. they are ac instead of dc
- D. they are digital only
296. Most FDM telemetry system use
- A. AM
- B. FM
- C. SSB
- D. PSK
297. In TDM, multiple signals
- A. share a common bandwidth
- B. modulate subcarriers
- C. are sampled at high speeds
- D. take turns transmitting
298. It is highly theoretical study of efficient use of bandwidth to propagate information through electronic communications system
- A. information capacity
- B. data communications
- C. information theory
- D. information technology
299. Another name for parity is
- A. Vertical redundancy check
- B. Block check character
- C. Longitudinal redundancy check
- D. Cyclic redundancy check
300. It is the process of gathering data on some particular phenomenon without the presence of human monitors
- A. Telemetry
- B. Telecommand
- C. Telecommunications
- D. Remote control
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